/*
 * Copyright (c) 2007, 2015, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package com.sun.org.apache.xml.internal.security.keys.content.keyvalues;

import java.math.BigInteger;
import java.security.Key;
import java.security.KeyFactory;
import java.security.NoSuchAlgorithmException;
import java.security.PublicKey;
import java.security.interfaces.DSAPublicKey;
import java.security.spec.DSAPublicKeySpec;
import java.security.spec.InvalidKeySpecException;

import com.sun.org.apache.xml.internal.security.exceptions.XMLSecurityException;
import com.sun.org.apache.xml.internal.security.utils.Constants;
import com.sun.org.apache.xml.internal.security.utils.I18n;
import com.sun.org.apache.xml.internal.security.utils.SignatureElementProxy;
import com.sun.org.apache.xml.internal.security.utils.XMLUtils;
import org.w3c.dom.Document;
import org.w3c.dom.Element;

public class DSAKeyValue extends SignatureElementProxy implements KeyValueContent {

  /**
   * Constructor DSAKeyValue
   */
  public DSAKeyValue(Element element, String baseURI) throws XMLSecurityException {
    super(element, baseURI);
  }

  /**
   * Constructor DSAKeyValue
   */
  public DSAKeyValue(Document doc, BigInteger P, BigInteger Q, BigInteger G, BigInteger Y) {
    super(doc);

    XMLUtils.addReturnToElement(this.constructionElement);
    this.addBigIntegerElement(P, Constants._TAG_P);
    this.addBigIntegerElement(Q, Constants._TAG_Q);
    this.addBigIntegerElement(G, Constants._TAG_G);
    this.addBigIntegerElement(Y, Constants._TAG_Y);
  }

  /**
   * Constructor DSAKeyValue
   */
  public DSAKeyValue(Document doc, Key key) throws IllegalArgumentException {
    super(doc);

    XMLUtils.addReturnToElement(this.constructionElement);

    if (key instanceof java.security.interfaces.DSAPublicKey) {
      this.addBigIntegerElement(((DSAPublicKey) key).getParams().getP(), Constants._TAG_P);
      this.addBigIntegerElement(((DSAPublicKey) key).getParams().getQ(), Constants._TAG_Q);
      this.addBigIntegerElement(((DSAPublicKey) key).getParams().getG(), Constants._TAG_G);
      this.addBigIntegerElement(((DSAPublicKey) key).getY(), Constants._TAG_Y);
    } else {
      Object exArgs[] = {Constants._TAG_DSAKEYVALUE, key.getClass().getName()};

      throw new IllegalArgumentException(I18n.translate("KeyValue.IllegalArgument", exArgs));
    }
  }

  /**
   * @inheritDoc
   */
  public PublicKey getPublicKey() throws XMLSecurityException {
    try {
      DSAPublicKeySpec pkspec =
          new DSAPublicKeySpec(
              this.getBigIntegerFromChildElement(
                  Constants._TAG_Y, Constants.SignatureSpecNS
              ),
              this.getBigIntegerFromChildElement(
                  Constants._TAG_P, Constants.SignatureSpecNS
              ),
              this.getBigIntegerFromChildElement(
                  Constants._TAG_Q, Constants.SignatureSpecNS
              ),
              this.getBigIntegerFromChildElement(
                  Constants._TAG_G, Constants.SignatureSpecNS
              )
          );
      KeyFactory dsaFactory = KeyFactory.getInstance("DSA");
      PublicKey pk = dsaFactory.generatePublic(pkspec);

      return pk;
    } catch (NoSuchAlgorithmException ex) {
      throw new XMLSecurityException("empty", ex);
    } catch (InvalidKeySpecException ex) {
      throw new XMLSecurityException("empty", ex);
    }
  }

  /**
   * @inheritDoc
   */
  public String getBaseLocalName() {
    return Constants._TAG_DSAKEYVALUE;
  }
}
